Whole-body metabolic tumour volume of 18F-FDG PET/CT improves the prediction of prognosis in small cell lung cancer

PET-Assessed Metabolic Tumor Volume Across the Spectrum of Solid-Organ Malignancies: A Review of the Literature

Solid-organ malignancies represent a significant disease burden and remain one of the leading causes of death globally. In the past few decades, the rapid evolution of imaging modalities has shifted the paradigm towards image-based precision medicine, especially in the care of patients with solid-organ malignancies. Metabolic tumor volume (MTV) is one such semi-quantitative parameter obtained from positron emission tomography (PET) imaging with 18F-fluorodeoxyglucose (FDG) that has been shown to have significant implications in the clinical oncology setting. Across various solid tumor malignancies, including lung cancer, head and neck cancer, breast cancer, esophageal cancer, and colorectal cancer, the current literature has demonstrated an association between MTV and various clinical outcomes. MTV may be used in conjunction with several existing and established clinical parameters to help inform risk stratification and treatment strategies and predict outcomes in cancer. Optimizing such volumetric parameters is paramount for advancing efforts to advance cancer care for our patients. While such advancements are made, it is important to investigate and address the limitations of MTV, including variability in terms of measurement methods, a lack of standardized cut-off values, and the impact of inherent tumor heterogeneity. Despite these limitations, which can precipitate challenges in standardization, MTV as a prognostic factor has great potential and opens an avenue for the future integration of technology into an image-based precision medicine model of care for cancer patients. This article serves as a narrative review and explores the utility and limitations of PET-MTV in various settings of solid-organ malignancy.

Potential role of pre-treatment bone marrow SUVmean to liver SUVmean ratio (BM/L) and comparison of primary tumour FDG uptake with brain FDG uptake in predicting survival in limited-stage lung cancers

INTRODUCTION

The survival rates of patients with limited-stage small-cell lung cancer are low despite curative treatment. Accordingly, we investigated the disease prognosis by comparing the pre-treatment bone marrow mean standardised uptake values (SUVmean) / liver SUVmean ratio (BM/L) and primary tumour FDG uptake and brain FDG uptake to prognosis.

MATERIALS AND METHODS

This was an observational, retrospective, single-centre study of patients with limited-stage small-cell lung cancer. Maximum standardised uptake values before treatment SUVmax, mean SUV (SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG), liver (KC) SUVmean, bone marrow SUVmean, BM/L ratio (grouped as BM/L <1 and BM/L<1), FDG uptake level of the primary tumour are higher than brain FDG uptake. The association of low prevalence with overall survival (OS) and progression-free survival (PFS) was evaluated.

DISCUSSION

A total of 125 patients were included in the study. The risk of death was found to be two times higher in patients with primary tumour FDG uptake higher than brain FDG uptake compared to those with less brain involvement. The risk of death in patients with BM/L>1 was found to be 1.6 times higher than in patients with BM/L<1.

CONCLUSION

Comparison of BM/L, FDG uptake of the primary tumour and brain FDG uptake as new prognostic parameters can be guiding in the classification of patients with LD-SCLC with a higher risk of death or progression and in planning new treatment strategies.

Primary tumor SUVmax and ratio of SUVmax to primary tumor size on pretreatment 18F-FDG-PET/CT scan in small cell lung cancer : Which is superior for the prognosis?

BACKGROUND

The prognostic impact of tumor SUVmax (t-SUVmax) in small cell lung cancer (SCLC) has been questioned with controversial results, and the significance of the ratio of tumor SUVmax to primary tumor size (SUVmax/t-size) in SCLC has yet to be clarified as well. In this study, a retrospective analysis was carried out to figure out the prognostic and predictive powers of pretreatment primary t‑SUVmax and t‑SUVmax/t-size ratio in patients with SCLC.

METHODS

A total of 349 SCLC patients who underwent pretreatment staging with PET/CT scan were enrolled in the study and analyzed retrospectively.

RESULTS

In limited disease SCLC (LD-SCLC), tumor size was significantly associated with both t‑SUVmax (p = 0.02) and t‑SUVmax/t-size (p = 0.0001). Furthermore, performance status, tumor size (p = 0.001), and liver metastasis were significantly associated with t‑SUVmax in extended disease SCLC (ED-SCLC). Moreover, tumor size (p = 0.0001), performance status, cigarette smoking history, and pulmonary/pleural metastasis were found to be correlated with t‑SUVmax/t-size. No associations were found between clinical stages and either t‑SUVmax or t‑SUVmax/t-size (p = 0.9 for both), and t‑SUVmax and t‑SUVmax/t-size values were found to have similar survival rates in both LD-SCLC and ED-SCLC patients. In univariate and multivariate analyses, both t‑SUVmax and t‑SUVmax/t-size were found not to be associated with overall survival (p > 0.05) CONCLUSION: This study does not advocate the use of either t‑SUVmax or t‑SUVmax/t-size on pretreatment 18F‑FDG-PET/CT scan as prognostic and predictive tools for both LD-SCLC and ED-SCLC patients. Likewise, we did not find that t‑SUVmax/t-size was superior to t‑SUVmax in that respect.

PI3K/AKT/mTOR pathway, hypoxia, and glucose metabolism: Potential targets to overcome radioresistance in small cell lung cancer

Small cell lung cancer (SCLC) is a highly aggressive tumor type for which limited therapeutic progress has been made. Platinum-based chemotherapy with or without thoracic radiotherapy remains the backbone of treatment, but most patients with SCLC acquire therapeutic resistance. Given the need for more effective therapies, better elucidation of the molecular pathogenesis of SCLC is imperative. The phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway is frequently activated in SCLC and strongly associated with resistance to ionizing radiation in many solid tumors. This pathway is an important regulator of cancer cell glucose metabolism, and its activation probably effects radioresistance by influencing bioenergetic processes in SCLC. Glucose metabolism has three main branches-aerobic glycolysis, oxidative phosphorylation, and the pentose phosphate pathway-involved in radioresistance. The interaction between the PI3K/AKT/mTOR pathway and glucose metabolism is largely mediated by hypoxia-inducible factor 1 (HIF-1) signaling. The PI3K/AKT/mTOR pathway also influences glucose metabolism through other mechanisms to participate in radioresistance, including inhibiting the ubiquitination of rate-limiting enzymes of the pentose phosphate pathway. This review summarizes our understanding of links among the PI3K/AKT/mTOR pathway, hypoxia, and glucose metabolism in SCLC radioresistance and highlights promising research directions to promote cancer cell death and improve the clinical outcome of patients with this devastating disease.

The value of the Standardized Uptake Value (SUV) and Metabolic Tumor Volume (MTV) in lung cancer

The diagnosis, staging and therapeutic monitoring of lung cancer were amongst the first applications for which the utility of FDG PET was documented and FDG PET/CT is now a routine diagnostic tool for clinical decision-making. As well as having high sensitivity for detection of disease sites, which provides critical information about stage, the intensity of uptake provides deeper biological characterization, while the burden of disease also has potential clinical significance. These disease characteristics can easily be quantified on delayed whole-body imaging as the maximum standardized uptake value (SUV_max) and metabolic tumor volume (MTV), respectively. There have been significant efforts to harmonize the measurement of these features, particularly within the context of clinical trials. Nevertheless, however calculated, in general, a high SUV_max and large MTV have been shown to have an adverse prognostic significance. Nevertheless, the use of these parameters in the interpretation and reporting of clinical scans remains inconsistent and somewhat controversial. This review details the current status of semi-quantitative FDG PET/CT in the evaluation of lung cancer.

Prognostic value of metabolic parameters on baseline 18F-FDG PET/CT in small cell lung cancer

BACKGROUND

Maximum standardized uptake value (SUV<inf>max</inf>) is the primary quantitave parameter given in 18F-FDG PET/CT reports. Calculations derived from three dimensional metabolic volumetric images have been proposed to be more successful than SUV<inf>max</inf> alone in prognostification with a lower interobserver variability in many cancers. We aimed to determine the prognostic value of metabolic parameters derived from 18F-FDG PET/CT studies in small cell lung cancer (SCLC) patient population with a long follow-up time.

METHODS

In this study, 38 consecutive SCLC patients (34M, 4F, age:65.76 ±8.18 years) who were referred to 18F-FDG PET/CT for staging between October 2006-January 2011 were included. SUV<inf>max</inf>, SUV<inf>mean</inf>, SUV<inf>peak</inf>, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were calculated. Overall survival (OS) was calculated from the date of the initial PET/CT to death from any cause. Survival tables were obtained and Kaplan Meier curves were reconstructed. Mantel-Cox regression analysis was performed in order to investigate if any of these parameters have an effect on survival along with other clinical risk factors.

RESULTS

Median SUV<inf>max</inf>, SUV<inf>mean</inf>, SUV<inf>peak</inf>, MTV, TLG and LDH values were calculated as 13.9 g/dL, 6.4 g/dL,10.69 g/dL, 147 cm³, 1898.52 and 375U/L respectively. Median follow-up was 761.23±873.21 days (25.37 months, range:110-3338 days). Since basal 18F-FDG PET/CT scans, all patients were lost in the follow-up except for two patients. MTV was a significant prognostic factor in SCLC patients. Estimated mean survival times were 261.0±45.6 (95% CI: 171.6-350.3) days in patients with MTV value above the calculated median 147, and 577.0±124.0 (95% CI: 333.7-820.2) days in patients with MTV<147. The difference was statistically significant with a P=0.037.

CONCLUSIONS

Baseline whole body MTV reflecting total tumor load is a prognostic index in SCLC. SUV is insufficient to predict prognosis.

Prognostic Value of Interim 18F-DOPA and 18F-FDG PET/CT Findings in Stage 3-4 Pediatric Neuroblastoma

PURPOSE

This retrospective study aimed to determine the prognostic value of imaging parameters derived from midtherapy 18F-fluorodihydroxyphenylalanine (18F-DOPA) and 18F-FDG PET in pediatric patients with stage 3-4 neuroblastoma.

METHODS

We enrolled 32 stage 3-4 pediatric neuroblastoma patients who underwent 18F-DOPA and 18F-FDG PET/CT scans before and after 3 chemotherapy cycles. We measured metabolic and volumetric parameters and applied a metabolic burden scoring system to evaluate the primary tumor extent and soft tissue metastases and that of bone/bone marrow involvement. The associations between these parameters and clinical outcomes were investigated.

RESULTS

Over a median follow-up period of 47 months (range, 3-137 months), 16 patients experienced disease progression, and 13 died. After adjustment for clinical factors, multivariate Cox proportional hazard models showed that interim tumor FDG/FDOPA SUVmax (hazard ratio [HR], 5.94; 95% confidence interval [CI], 1.10-34.98) and interim FDOPA whole-body metabolic burden scores (WBMB) (HR, 7.30; 95% CI, 1.50-35.50) were significant prognostic factors for overall survival (OS). Only interim FDOPA WBMB scores (HR, 7.05; 95% CI, 1.02-48.7) were predictive of progression-free survival. Based on median cutoff values, prognosis (OS and progression-free survival) was significantly associated with an interim FDOPA WBMB score ≥21.92 (all P < 0.05) and interim tumor FDG/FDOPA (SUVmax) score ≥0.57 with poor OS (P < 0.05).

CONCLUSIONS

Our results indicate that midtreatment FDG and FDOPA PET/CT could serve as prognostic markers in stage 3-4 neuroblastoma patients.

The value of preoperative 18F-FDG PET metabolic and volumetric parameters in predicting microvascular invasion and postoperative recurrence of hepatocellular carcinoma

BACKGROUND

Microvascular invasion (MVI) is very important in the evaluation of hepatocellular carcinoma (HCC), but diagnosis is determined by postoperative pathology; thus, preoperative noninvasive methods will play an active role. The purpose of the study was to assess the performance of metabolic parameters of preoperative 18F-fluorodeoxyglucose PET/computerized tomography (18F-FDG PET/CT) in the prediction of MVI and postoperative recurrence in primary hepatocellular carcinoma.

METHODS

We retrospectively collected 72 patients with HCC who have performed 18F-FDG PET/CT scan before partial hepatectomy between 2016 and 2019. We used both normal liver tissue and inferior vena cava as the reference background and combined with clinicopathological features, 18F-FDG PET/CT metabolic and volumetric indices to predict MVI and postoperative recurrence of primary HCC before surgery.

RESULTS

Twenty-one of the 72 patients recurred, in recurrent cases showed higher maximum standard uptake value (SUVmax), TNR (ratio of tumor SUVmax to mean SUV [SUVmean] of the background tissue), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) than nonrecurrence cases (P < 0.001). All 18F-FDG PET metabolic and volumetric indices for predicting postoperative HCC recurrence were significant on receiver-operating-characteristic (ROC) curve analyses (P < 0.05). TNRIVC, TNRNL, MTVIVC, MTVNL TLGIVC and TLGNL were significant factors for predicting MVI in HCC (P < 0.05). On multivariate analyses, MVI, SUVmax, TNRIVC, TNRNL, MTVIVC, MTVNL, TLGIVC and TLGNL (P < 0.05) are independent risk factors for predicting postoperative HCC recurrence. TNRIVC is the most relevant PET/CT parameter for predicting MVI in HCC, and MTVIVC is the most valuable for predicting postoperative HCC recurrence. Moreover, the PET/CT parameters are more accurate for prognosis with inferior vena cava as a reference background than with normal liver tissue.

CONCLUSION

18F-FDG PET/CT metabolic and volumetric indices are effective predictors, and could noninvasively provide more comprehensive predictive information on MVI and postoperative recurrence of primary HCC before surgery.

Progression and metastasis of small cell lung carcinoma: the role of the PI3K/Akt/mTOR pathway and metabolic alterations

Small cell lung carcinoma (SCLC) is characterized by high metastatic rate and poor prognosis. The platinum-based chemotherapy still represents the backbone of the therapy; however, acquired resistance develops almost in all patients. Although SCLC has been formerly considered a homogeneous disease, recent advances in SCLC research have highlighted the importance of inter- and intratumoral heterogeneity and have resulted in the subclassification of SCLC. The newly described SCLC subtypes are characterized by distinct biological behavior and vulnerabilities that can be therapeutically exploited. The PI3K/Akt/mTOR pathway is frequently affected in SCLC, and its activation represents a promising therapeutic target. Since the mTOR pathway is a master regulator of cellular metabolism, its alterations may also influence the bioenergetic processes of SCLC cells. Despite the encouraging preclinical results, both mTOR and metabolic inhibitors have met limited clinical success so far. Patient selection for personalized therapy, the development of rational drug combinations, and a better understanding of heterogeneity and spatiotemporal evolution of the tumor cells may improve efficacy and can help to overcome acquired resistance. Here we provide a summary of current investigations regarding the role of the mTOR pathway and metabolic alterations in the progression and metastasis formation of SCLC.

Identification of Stage IIIC/IV EGFR-Mutated Non-Small Cell Lung Cancer Populations Sensitive to Targeted Therapy Based on a PET/CT Radiomics Risk Model

Objectives

This project aimed to construct an individualized PET/CT prognostic biomarker to accurately quantify the progression risk of patients with stage IIIC-IV epidermal growth factor receptor (EGFR)-mutated Non-small cell lung cancer (NSCLC) after first-line first and second generation EGFR- tyrosine kinase inhibitor (TKI) drug therapy and identify the first and second generation EGFR-TKI treatment-sensitive population.

Methods

A total of 250 patients with stage IIIC-IV EGFR-mutated NSCLC underwent first-line first and second generation EGFR-TKI drug therapy were included from two institutions (140 patients in training cohort; 60 patients in internal validation cohort, and 50 patients in external validation cohort). 1037 3D radiomics features were extracted to quantify the phenotypic characteristics of the tumor region in PET and CT images, respectively. A four-step feature selection method was performed to enable derivation of stable and effective signature in the training cohort. According to the median value of radiomics signature score (Rad-score), patients were divided into low- and high-risk groups. The progression-free survival (PFS) behaviors of the two subgroups were compared by Kaplan–Meier survival analysis.

Results

Our results shown that higher Rad-scores were significantly associated with worse PFS in the training (p < 0.0001), internal validation (p = 0.0153), and external validation (p = 0.0006) cohorts. Rad-score can effectively identify patients with a high risk of rapid progression. The Kaplan–Meier survival curves of the three cohorts present significant differences in PFS between the stratified slow and rapid progression subgroups.

Conclusion

The PET/CT-derived Rad-score can realize the precise quantitative stratification of progression risk after first-line first and second generation EGFR-TKI drug therapy for NSCLC and identify EGFR-mutated NSCLC populations sensitive to targeted therapy, which might help to provide precise treatment options for NSCLC.

Value of pretreatment serum lactate dehydrogenase as a prognostic and predictive factor for small-cell lung cancer patients treated with first-line platinum-containing chemotherapy

BACKGROUND

The current study aimed to evaluate the serum pretreatment lactate dehydrogenase (LDH) and overall survival (OS) in small cell lung cancer (SCLC) patients who received first-line platinum-containing chemotherapy.

METHODS

A total of 234 SCLC patients, who received first-line platinum-based chemotherapy between 2013 and 2018, were retrospectively analyzed. The data of hematological characteristics, age, gender, ECOG score, staging, metastatic site, smoking history, chemotherapy cycle, thoracic radiotherapy and hyponatremia were collected. Overall survival was calculated using the Kaplan-Meier method. The statistically significant factors in the univariate analysis were selected for the multivariate COX model analysis.

RESULTS

Age, ECOG score, stage, thoracic radiotherapy, hyponatremia, liver metastasis, brain metastasis, bone metastasis, LDH, NSE and neutrophil-to-lymphocyte ratio (NLR) were closely correlated to OS in the univariate analysis. Furthermore, the multivariate analysis revealed that age (<65 years), ECOG score (<2 points), limited-stage (LD), thoracic radiotherapy and LDH <215.70 U/L were the independent prognostic factors for survival. The median OS time was worse for patients with LDH ≥215.70 U/L. In the subgroup analysis, LDH ≥215.70 U/L was significant for survival in both limited and extensive disease. Patients who achieved CR + PR in the first-line treatment had lower initial LDH levels. It was found that the pretreatment LDH increased the incidence of patients with liver metastasis.

CONCLUSIONS

Positive independent prognostic factors for SCLC patients were age < 65 years old, ECOG score < 2 points, LD-SCLC, and pretreatment LDH <215.70 U/L. These factors may be useful for stratifying patients with SCLC for treatment approaches.

KEY POINTS

SIGNIFICANT FINDINGS OF THE STUDY: Age < 65 years old, ECOG score < 2 points, LD-SCLC, and pretreatment LDH <215.70 U/L are the positive independent prognostic factors for SCLC patients.

WHAT THIS STUDY ADDS

The current study provided more references for SCLC diagnosis and treatment and determined more factors for stratifying patients with SCLC for treatment approaches.

KSNM60 in Clinical Nuclear Oncology

Since the foundation of the Korean Society of Nuclear Medicine in 1961, clinical nuclear oncology has been a major part of clinical nuclear medicine in Korea. There are several important events for the development of clinical nuclear oncology in Korea. First, a scintillating type gamma camera was adopted in 1969, which enabled to perform modern oncological gamma imaging. Second, Tc-99 m generator was imported to Korea since 1979, which promoted the wide clinical use of gamma camera imaging by using various kinds of Tc-99 m labeled radiopharmaceuticals. Third, a gamma camera with single photon emission tomography (SPECT) capability was first installed in 1980, which has been used for various kinds of tumor SPECT imaging. Fourth, in 1994, clinical positron emission tomography (PET) scanner and cyclotron with a production of F-18 fluorodeoxyglucose were first installed in Korea. Fifth, Korean Board of Nuclear Medicine was established in 1995, which contributed in the education and manpower training of dedicated nuclear medicine physicians in Korea. Finally, an integrated PET/CT scanner was first installed in 2002. Since that, PET/CT imaging has been a major imaging tool in clinical nuclear oncology in Korea. In this review, a brief history of clinical nuclear oncology in Korea is described.

Prediction of Neoadjuvant Chemotherapy Response in Osteosarcoma Using Convolutional Neural Network of Tumor Center 18F-FDG PET Images

We compared the accuracy of prediction of the response to neoadjuvant chemotherapy (NAC) in osteosarcoma patients between machine learning approaches of whole tumor utilizing fluorine−¹⁸fluorodeoxyglucose (¹⁸F-FDG) uptake heterogeneity features and a convolutional neural network of the intratumor image region. In 105 patients with osteosarcoma, ¹⁸F-FDG positron emission tomography/computed tomography (PET/CT) images were acquired before (baseline PET0) and after NAC (PET1). Patients were divided into responders and non-responders about neoadjuvant chemotherapy. Quantitative ¹⁸F-FDG heterogeneity features were calculated using LIFEX version 4.0. Receiver operating characteristic (ROC) curve analysis of ¹⁸F-FDG uptake heterogeneity features was used to predict the response to NAC. Machine learning algorithms and 2-dimensional convolutional neural network (2D CNN) deep learning networks were estimated for predicting NAC response with the baseline PET0 images of the 105 patients. ML was performed using the entire tumor image. The accuracy of the 2D CNN prediction model was evaluated using total tumor slices, the center 20 slices, the center 10 slices, and center slice. A total number of 80 patients was used for k-fold validation by five groups with 16 patients. The CNN network test accuracy estimation was performed using 25 patients. The areas under the ROC curves (AUCs) for baseline PET maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), metabolic tumor volume (MTV), and gray level size zone matrix (GLSZM) were 0.532, 0.507, 0.510, and 0.626, respectively. The texture features test accuracy of machine learning by random forest and support vector machine were 0.55 and 0. 54, respectively. The k-fold validation accuracy and validation accuracy were 0.968 ± 0.01 and 0.610 ± 0.04, respectively. The test accuracy of total tumor slices, the center 20 slices, center 10 slices, and center slices were 0.625, 0.616, 0.628, and 0.760, respectively. The prediction model for NAC response with baseline PET0 texture features machine learning estimated a poor outcome, but the 2D CNN network using ¹⁸F-FDG baseline PET0 images could predict the treatment response before prior chemotherapy in osteosarcoma. Additionally, using the 2D CNN prediction model using a tumor center slice of ¹⁸F-FDG PET images before NAC can help decide whether to perform NAC to treat osteosarcoma patients.

[18F]FDG PET/MRI enables early chemotherapy response prediction in pancreatic ductal adenocarcinoma

Purpose

In this prospective exploratory study, we evaluated the feasibility of [¹⁸F]fluorodeoxyglucose ([¹⁸F]FDG) PET/MRI-based chemotherapy response prediction in pancreatic ductal adenocarcinoma at two weeks upon therapy onset.

Material and methods

In a mixed cohort, seventeen patients treated with chemotherapy in neoadjuvant or palliative intent were enrolled. All patients were imaged by [¹⁸F]FDG PET/MRI before and two weeks after onset of chemotherapy. Response per RECIST1.1 was then assessed at 3 months [¹⁸F]FDG PET/MRI-derived parameters (MTV_50%, TLG_50%, MTV_2.5, TLG_2.5, SUV_max, SUV_peak, ADC_max, ADC_mean and ADC_min) were assessed, using multiple t-test, Man–Whitney-U test and Fisher’s exact test for binary features.

Results

At 72 ± 43 days, twelve patients were classified as responders and five patients as non-responders. An increase in ∆MTV_50% and ∆ADC (≥ 20% and 15%, respectively) and a decrease in ∆TLG_50% (≤ 20%) at 2 weeks after chemotherapy onset enabled prediction of responders and non-responders, respectively. Parameter combinations (∆TLG_50% and ∆ADC_max or ∆MTV_50% and ∆ADC_max) further improved discrimination.

Conclusion

Multiparametric [¹⁸F]FDG PET/MRI-derived parameters, in particular indicators of a change in tumor glycolysis and cellularity, may enable very early chemotherapy response prediction. Further prospective studies in larger patient cohorts are recommended to their clinical impact.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13550-021-00808-4.

Combining Lactate Dehydrogenase and Fibrinogen: Potential Factors to Predict Therapeutic Efficacy and Prognosis of Patients with Small-Cell Lung Cancer

Background

A growing interest exists in identifying reliable and low-cost biomarkers or factors that could predict the therapeutic response, prognosis, recurrence, and survival in small-cell lung cancer (SCLC). This study aimed to investigate the better predictors of chemotherapy efficacy and prognosis in patients with SCLC receiving first-line chemotherapy and radiotherapy.

Materials and Methods

This study retrospectively retrieved the medical records of patients with SCLC treated with first-line platinum-based chemotherapy and radiotherapy from January 2016 to June 2019 in the First Affiliated Hospital of Nanjing Medical University. Plasma biochemical parameters, clinical features, and overall survival (OS) time were collected. The independent effects of plasma parameters on patient survival were assessed by conducting univariate and multivariate Cox regression analyses. The optimal cut-off values of independent risk factors in the ROC curve and Kaplan–Meier survival analysis were determined using MedCalc software.

Results

Statistically significant differences in lactate dehydrogenase (LDH) and fibrinogen (Fbg) were found between the complete remission + partial remission group and the non-responders, which consisted of stable-disease and progressive-disease groups, after first-line chemotherapy. Multivariate Cox regression analysis showed that LDH and Fbg were independent risk factors in predicting PFS (LDH HR: 1.013, 95% CI: 1.002–1.030, P = 0.037; Fbg HR: 1.622, 95% CI: 1.094–2.526, P = 0.017) and OS (LDH HR: 1.021, 95% CI: 1.008–1.034, P = 0.001; Fbg HR: 2.168, 95% CI: 1.324–3.550, P = 0.002). The AUC of LDH and Fbg was 0.77 and 0.745, respectively. The cut-off value of LDH and Fbg in predicting OS was 263 U/L and 4.03 g/L. When these two data were combined, the AUC reached 0.832, better than that of LDH and Fbg alone. The objective response rate (ORR) and OS were significantly different among these three different groups according to the addition of the assigned value (P < 0.05).

Conclusion

Combined retreatment serum LDH and Fbg levels may be a better potential biomarker for predicting the clinical efficacy of chemotherapy and the prognosis of individuals with SCLC. Combining these two parameters could improve prediction efficacy.

One Versus Up-to-5 Lesion Measurements for Response Assessment by PERCIST in Patients with Lung Cancer

Purpose

The optimal number of lesions to measure for response assessment from fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) is not validated for lung cancer. We compared 1 lesion and up-to-5 lesion measurements for response assessment in lung cancer per PET Response Criteria in Solid Tumors (PERCIST).

Methods

Patients with lung cancer with pre- and post-treatment PET/CT images were included. The standard uptake value corrected for lean body mass (SUL_peak) of up-to-5 hottest target lesions was measured at each time point. The percent changes of SUL_peak of the single hottest lesion and the sum of up-to-5 hottest lesions were computed. Pearson correlation coefficient evaluated the strength of association between the percent changes of SUL_peak values from the 1 lesion and up-to-5 lesion analyses. Response categories were complete metabolic response (CMR) with no perceptible lesion; partial metabolic response (PMR), stable metabolic disease (SMD), or progressive metabolic disease (PMD) using the threshold of 30% and 0.8 unit change in SUL_peak; and unequivocal new lesion meant PMD. The concordance for response categorization was assessed by kappa statistics.

Results

A total of 40 patients (25 non-small cell lung cancer; 15 small cell lung cancer) were analyzed, all with ¹⁸F-FDG-avid lung cancer. Average of 3 target lesions were measured for up-to-5 lesion analysis. Pearson's r was 0.74 (P < 0.001) and increased to 0.96 (P < 0.001) when two outliers were excluded. Response categorization with 1 lesion and up-to-5 lesion analyses was concordant in 37 patients (92.5%, weighted kappa = 0.89).

Conclusion

Analyzing 1 lesion and up-to-5 lesions for response assessment by PERCIST showed high concordance in patients with lung cancer.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13139-021-00697-4.

Prognostic Significance of Metabolic Parameters by 18F-FDG PET/CT in Thymic Epithelial Tumors

Simple Summary

Thymic epithelial tumors have variable prognoses that depend on histological subtype, and ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) currently plays an important part in oncology images. Thus, we prosecuted a retrospective review of data from 83 patients with thymic epithelial tumors who underwent pretreatment ¹⁸F-FDG PET/CT and investigated the prognostic significance along with WHO classification, Masaoka stage, and volumetric ¹⁸F-PET parameters. Masaoka stage, histologic type, treatment modality, maximum standardized uptake values (SUV_max), average standardized uptake values (SUV_avg), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were significant prognostic factors for time-to-progression on univariate survival analysis. On multivariate analysis, SUV_avg and Masaoka stage were important independent prognostic factors for progression-free survival in thymic epithelial tumors.

Abstract

Background: Imaging tumor FDG avidity could complement prognostic implication in thymic epithelial tumors. We thus investigated the prognostic value of volume-based ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/CT parameters in thymic epithelial tumors with other clinical prognostic factors. Methods: This is a retrospective study that included 83 patients who were diagnosed with thymic epithelial tumors and underwent pretreatment ¹⁸F-FDG PET/CT. PET parameters, including maximum and average standardized uptake values (SUV_max, SUV_avg), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), were measured with a threshold of SUV 2.5. Univariate and multivariate analysis of PET parameters and clinicopathologic variables for time-to-progression was performed by using a Cox proportional hazard regression model. Results: There were 21 low-risk thymomas (25.3%), 27 high-risk thymomas (32.5%), and 35 thymic carcinomas (42.2%). Recurrence or disease progression occurred in 24 patients (28.9%). On univariate analysis, Masaoka stage (p < 0.001); histologic types (p = 0.009); treatment modality (p = 0.001); and SUV_max, SUV_avg, MTV, and TLG (all p < 0.001) were significant prognostic factors. SUV_avg (p < 0.001) and Masaoka stage (p = 0.001) were independent prognostic factors on multivariate analysis. Conclusion: SUV_avg and Masaoka stage are independent prognostic factors in thymic epithelial tumors.

Prognostic Value of 18F-FDG-PET Parameters in Patients with Small Cell Lung Cancer: A Meta-Analysis and Review of Current Literature

Many studies have suggested a prognostic value of one or several positron emission tomography (PET) parameters in patients with small cell lung cancer (SCLC). However, studies are often small, and there is a considerable interstudy disagreement about which PET parameters have a prognostic value. The objective of this study was to perform a review and meta-analysis to identify the most promising PET parameter for prognostication. PubMed^®, Cochrane, and Embase^® were searched for papers addressing the prognostic value of any PET parameter at any treatment phase with any endpoint in patients with SCLC. Pooled hazard ratios (HRs) were calculated by a random effects model for the prognostic value of the baseline maximum standardized uptake value (SUV_max) and metabolic tumor volume (MTV). The qualitative analysis included 38 studies, of these, 19 studies were included in the meta-analyses. The pooled results showed that high baseline MTV was prognostic for overall survival (OS) (HR: 2.83 (95% confidence interval [CI]: 2.00–4.01) and progression-free survival (PFS) (HR: 3.11 (95% CI: 1.99–4.90)). The prognostic value of SUV_max was less pronounced (OS: HR: 1.50 (95% CI: 1.17–1.91); PFS: HR: 1.24 (95% CI: 0.94–1.63)). Baseline MTV is a strong prognosticator for OS and PFS in patients with SCLC. MTV has a prognostic value superior to those of other PET parameters, but whether MTV is superior to other prognosticators of tumor burden needs further investigation.

Combining 18F-FDG PET/CT and Serum Lactate Dehydrogenase for Prognostic Evaluation of Small Cell Lung Cancer

Objective: To investigate the value of using ¹⁸F-FDG PET/CT in combination with serum lactate dehydrogenase (LDH) for prognostic evaluation of newly diagnosed small cell lung cancer (SCLC). Methods: We reviewed 118 patients with pathologically proven SCLC who underwent ¹⁸F-FDG PET/CT imaging evaluation in our hospital. Among these patients, 64 patients had extensive disease (ED) and 54 patients had limited disease (LD). The maximum standardized uptake value (SUV_max) of primary tumor was measured. A Cox proportional hazards model was used to evaluate age, sex, performance status, serum LDH, tumor stage and SUV_max on the prediction of overall survival (OS) and median survival time (MST) of patients. Subgroup analysis was performed based on the SUV_max in combination with serum LDH. Results: According to the Receiver Operating Characteristic (ROC) curve, the optimal cut-off value of SUV_max was 10.95. The AUC was 0.535 (95% CI: 0.407-0.663). The patients were divided into four groups according to the SUV_max (higher or lower than 10.95) and LDH (higher or lower than 245 U/L). The univariate and multivariate analyses showed that curative thoracic radiotherapy, Prophylactic Cranial Irradiation (PCI) and the combination of primary tumor SUV_max ≤ 10.95 and LDH ≤ 245 U/L were prognostic factors of OS in patients with all patients (p < 0.05). Smoking status, PCI, the combination of primary tumor SUV_max ≤ 10.95 and LDH ≤ 245 U/L were prognostic factors of OS in patients with LD (p < 0.05). N stage and PCI were significant predictors in both of univariate and multivariate analysis of OS for ED SCLC (p < 0.05). Among all patients, 27 had low SUV_max and normal LDH, and their MST was 36 months (95% CI: 12.98-59.02). Ninety-one patients had high SUV_max and/or high LDH, and their MST was 20 months (95% CI: 15.47-24.53). The difference between these two groups was significant (p = 0.045). In patients with LD, 16 patients had low SUV_max and normal LDH, and their MST was 72 months (95% CI: 26.00-118.0). Thirty-eight patients had high SUV_max and/or high LDH, and their MST was 27 months (95% CI: 20.80-33.21). The difference between these two groups was significant (p = 0.012). In patients with ED SCLC, 10 patients had low SUV_max and normal LDH, with an MST of 18 months (95% CI: 13.69-22.32. Fifty-four patients had high SUV_max and/or high LDH, and their MST was 12 months (95% CI: 10.61-13.39). The difference of MST between these two groups was not statistically significant (p = 0.686). Conclusion: ¹⁸F-FDG PET/CT in combination with serum LDH were prognostic factors of overall survival in patients with SCLC. The prognosis of patients with LD SCLC who had low SUV_max of primary tumor and normal LDH was better than those with high SUV_max and/or high LDH.

A New Prognostic Index Combines the Metabolic Response and RECIST 1.1 to Evaluate the Therapeutic Response in Patients With Non-Small Cell Lung Cancer

Aim: Response Evaluation Criteria in Solid Tumors (RECIST) is occasionally insufficient for evaluation. We proposed a new prognostic index (NPI) that combines the standardized uptake value (SUV), metabolic tumor volume (MTV), and RECIST. Methods: In total, 116 patients with lung cancer who underwent consecutive positron emission tomography-computed tomography prior to and after the initial treatment were included. We formulated the NPI by estimating the hazard ratios of overall survival for ΔMTV, ΔSUVmax, and ΔD (tumor size based on RECIST). Progression-free survival (PFS) and overall survival (OS) were compared between RECIST and the NPI. Results: ROC curve analysis identified two cutoff values based on the NPI (≤ -49.3% and ≥43.4%) to discriminate partial remission (NPR), stable disease (NSD) and progressive disease (NPD). Based on RECIST, survival analysis did not discriminate significantly on either PFS or OS between the PR, SD, and PD groups. However, according to the NPI, PFS and OS differed significantly between the NPR, NSD, and NPD groups (training set: PFS, p = 0.048; OS, p = 0.026; validation set: PFS, p = 0.004; OS, p = 0.023). Moreover, therapeutic response based on NPI was independent prognostic factor for both PFS [NPR as reference, NSD: hazard ratio (HR) 2.04; 95% confidence interval (95% CI) 1.35-3.08; p = 0.001; NPD: HR 6.87; 95% CI 3.03-15.57; p < 0.001] and OS (NPR as reference, NSD: HR 1.64; 95% CI 1.05-2.57; p = 0.031; NPD: HR 3.56; 95% CI 1.59-7.95; p = 0.002). Conclusion: The NPI showed superiority for evaluation of the therapeutic response and survival for patients with non-small cell lung cancer, overcoming the limitations of RECIST.

Positron emission tomography/computed tomography using 2-deoxy-2-fluoro-18-fluoro-D-glucose peri-tumoral halo uptake layer method outperforms magnetic resonance imaging and ultrasound methods in tumor size measurement of breast cancer

As a non-invasive method, positron emission tomography (PET)/computed tomography (CT) using 2-deoxy-2-fluoro-18-fluoro-D-glucose (18F-FDG) is applied as a useful modality in the diagnosis of breast cancer. By evaluating glucose metabolism, this method can also be used in staging, restaging and post-therapeutic response evaluation. To evaluate the reliability of the ¹⁸F-FDG PET/CT-based peri-tumoral halo uptake layer (PHL) method for assessing tumor size, a total of 79 female patients with breast cancer who underwent ¹⁸F-FDG PET/CT, breast ultrasound and magnetic resonance imaging (MRI) evaluations were included in the present study. Upon examination by two independent nuclear medicine radiologists, tumor sizes were estimated by ¹⁸F-FDG PET/CT using margins defined as the inner line of the PHL. Pathological tumor sizes were evaluated on the direction of largest diameter indicated by previous imaging examination, which were also utilized as final standards. Statistical analysis of the results suggested that ¹⁸F-FDG PET/CT had a more linear correlation with pathology compared with breast ultrasound (r²=0.89 vs. 0.73) and MRI (r²=0.89 vs. 0.69) in terms of tumor size estimation, including a significantly lower bias in size difference relative to pathology. ¹⁸F-FDG PET/CT also exhibited improved performance compared with breast ultrasound and MRI in T stage assessment. These results indicated that the ¹⁸F-FDG PET/CT-based PHL method was superior to breast ultrasound and MRI, and that it provides sufficient reliability and high accuracy for measuring tumor size in patients with breast cancer.

Prognostic value of 18F-FDG PET/CT metabolic parameters in small cell lung cancer

Objective

To compare the prognostic values of metabolic parameters from pretreatment PET/CT between limited disease (LD) and extensive disease (ED) small cell lung cancer (SCLC) patients.

Methods

Data on 118 newly diagnosed SCLC patients (50 LD and 68 ED) who underwent pretreatment positron emission tomography–computed tomography (PET/CT) were reviewed. For PET, metabolic parameters were measured for: (1) primary tumor, maximum standardized uptake value (SUVmax), metabolic tumor volume, and total lesion glycolysis; and (2) all tumor lesions, SUVmax of the hottest tumor, whole body metabolic tumor volume (WBMTV), and whole body total lesion glycolysis (WBTLG). Prognostic values of metabolic parameters and other clinical variables were analyzed to predict overall survival (OS).

Results

In LD, SUVmax of the primary tumor was an independent prognostic factor for OS. Patients with high SUVmax showed significantly worse OS than those with low SUVmax. In ED, WBMTV and WBTLG were independent prognostic factors for OS. Patients with high WBMTV or WBTLG showed significantly worse OS than those with low WBMTV or WBTLG.

Conclusions

SUVmax of primary tumor was the only independent prognostic factor for OS in LD SCLC patients. WBMTV and WBTLG were independent prognostic factors in ED SCLC patients.

The prognostic role of PET/CT in small-cell lung cancer

OBJECTIVE

The aim in the present study is to determine the prognostic value of metabolic parameters related to the primary tumors detected in pretreatment Fluorine-18 2-fluoro-2-Deoxy-D-glucose (¹⁸F FDG) positron emission tomography/computerized tomography (PET/CT) scans of patients diagnosed with small-cell lung cancer (SCLC).

MATERIAL AND METHODS

Enrolled in this retrospective study were 63 patients with a histopathologically confirmed diagnosis of SCLC who underwent an ¹⁸F FDG PET/CT scan at baseline. Disease stage, age at diagnosis, gender, albumin level and maximum standardized uptake value (SUVmax), SUVmean, metabolic tumor volume (MTV) and total lesion glycolysis (TLG) values related to the primary tumor at the baseline PET scan were recorded, and the relationship of these factors with progression-free survival (PFS) and overall survival (OS) was evaluated.

RESULTS

The study included a total of 63 patients (10 female, 53 male, mean age of 64.8 and age range of 43-82 years), 22 of which had limited disease (LD) and 41 had extensive disease (ED). The OS and PFS were significantly higher in patients with LD than in patients with ED (15±2.9 vs. 10±0.9 months, p = 0.002 for OS; 10± 0.7 vs 6±0.6 months, p = 0.014 for PFS). However, no statistically significant relationship was identified between gender, albumin level, age and SUVmax, SUVmean, MTV, TLG values related to the primary tumor and PFS or OS.

CONCLUSION

The present study found that pretreatment PET parameters were of not predictive value for PFS and OS in patients with SCLC.

Prognostic and diagnostic value of [18F]FDG-PET/CT in restaging patients with small cell lung carcinoma: an Italian multicenter study

BACKGROUND

The presence of residual disease after initial treatment in small cell lung cancer (SCLC) influences prognosis and impacts patient management. To date, few data exist on the value of fluorine-18-fluorodeoxyglucose ([F]FDG)-PET/computed tomography (CT) in SCLC at restaging. Therefore, in restaging patients with SCLC, we aimed to (a) evaluate the prognostic value yielded by [F]FDG-PET/CT and (b) assess the diagnostic agreement between [F]FDG-PET/CT and contrast-enhanced computed tomography (ceCT).

PATIENTS AND METHODS

From a multicenter database, we evaluated 164 patients with SCLC who underwent [F]FDG-PET/CT for restaging purposes. PET scans were evaluated visually to identify the presence of recurrence. For each patient, the maximum and the mean standardized uptake value (SUVmax and SUVmean, respectively), metabolic tumor volume, and total lesion glycolysis were calculated, taking into account the lesion with the highest [F]FDG uptake (namely, the index lesion) in the local recurrences, lymph node involvement, and distant metastasis categories. Kaplan-Meier curves were computed to assess the effects of [F]FDG-PET/CT findings on overall survival (OS) and progression-free survival. Furthermore, the agreement between PET/CT and ceCT in detecting metastases was evaluated in 119 patients on a patient-based analysis (Cohen's κ; P < 0.05).

RESULTS

The presence of metastatic lesions at [F]FDG-PET/CT was associated with a significantly shorter OS (P = 0.039) and progression-free survival (P < 0.001). Higher SUVmax showed a trend toward a shorter OS (P = 0.065). The K-agreement between ceCT and PET/CT in recurrent SCLC was 0.37 (P < 0.001). PET/CT and ceCT showed the same number of lesions in 52 (43.7%) patients, whereas PET/CT detected additional lesions in 35 (29.4%) patients.

CONCLUSION

Detection of metastatic lesions at restaging by [F]FDG-PET/CT can predict a higher rate of progression and negatively influence OS in patients with SCLC. [F]FDG-PET/CT and ceCT seem to be complementary imaging modalities in patients with metastatic SCLC.

Significance of Metabolic Tumor Volume and Total Lesion Glycolysis Measured Using ¹⁸F-FDG PET/CT in Locally Advanced and Metastatic Gallbladder Carcinoma

PURPOSE

This study aimed to determine the prognostic value of new quantitative parameters of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT), including metabolic tumor volume (MTV), in patients with locally advanced and metastatic gallbladder cancer (GBC).

MATERIALS AND METHODS

In total, 83 patients initially diagnosed with locally advanced and metastatic GBC and who underwent ¹⁸F-FDG PET/CT at the time of initial diagnosis were retrospectively reviewed. The metabolic volume-based PET parameters of primary tumors and metastatic lesions were measured, including maximum and average standardized uptake values (SUV), MTV, and total lesion glycolysis. An overall survival (OS) analysis was performed using the Kaplan-Meier method with PET and clinical parameters. A Cox proportional hazards regression analysis was performed to determine independent prognostic factors.

RESULTS

In univariate analysis, pathologic differentiation (p<0.001), performance status (PS; p=0.003), C-reactive protein (CRP) level (p=0.009), and PET-related SUV_{mt max} (the highest SUV among the metastatic lesions) (p=0.040) and MTV_total (the sum of the MTVs of both the primary and metastatic lesions) (p=0.031), were significant for OS. In multivariate analysis, MTV_total (hazard ratio: 2.07; 95% confidence interval: 1.23-3.48; p=0.006) remained significant for the prediction of OS, as did differentiation (p=0.001), PS (p=0.001), and CRP (p=0.039).

CONCLUSION

In locally advanced and metastatic GBC, volume-based PET/CT parameters of the total tumor burden of malignancy, such as MTV_total, were found to be useful for the identification of patients with poor prognosis.

Prognostic significance of metabolic parameters measured by 18F-FDG PET/CT in limited-stage small-cell lung carcinoma

PURPOSE

Metabolic parameters measured by [18F]-fluorodeoxyglucose-positron emission tomography/computed tomography (18F-FDG PET/CT) are important prognostic factors in several types of cancers. We evaluated the predictive value of tumor metabolic parameters measured by 18F-FDG PET/CT in limited-disease small-cell lung cancer (LD-SCLC).

METHODS

This retrospective study included 30 LD-SCLC patients who underwent standard chemotherapy after radiotherapy with 18F-FDG PET/CT. The maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and blood glucose-corrected values were used to evaluate metabolic parameters in primary tumors.

RESULTS

For the median follow-up of 41.1 months, median overall survival (OS) was 75.0 months [95% confidence interval (CI) 20.9-129.1 months], and median progression-free survival (PFS) was 9.5 months (95% CI 6.8-12.1 months). Two-year OS was 78.6%, and PFS was 32.7%. OS analysis indicated that MTV and TLG were significant predictors of OS following standard treatment. High glucose-corrected SUVmax (glu-SUVmax) was related to shorter median PFS. On multivariate analysis, MTV was an independent factor of OS, and glu-SUVmax was significantly related to PFS.

CONCLUSIONS

MTV and glu-SUVmax measured on pretreatment 18F-FDG PET/CT were independent prognostic factors for LD-SCLC patients after chemoradiotherapy with curative intent. These metabolic markers need validation in larger prospective studies but may be useful in the clinical care of LD-SCLC patients.

Correlation study on 18F-FDG PET/CT metabolic characteristics of primary lesion with clinical stage in lung cancer

BACKGROUND

¹⁸F-FDG PET/CT metabolic characteristics provide the crucial biologic and molecular information for tumors. To explore the relationships between ¹⁸F-FDG PET/CT derived parameters such as maximum standardized uptake value (SUV<inf>max</inf>), metabolic tumor volume (MTV), total lesion glycolysis (TLG) of primary tumor and clinical stage in different histopathologic subtypes of lung cancer.

METHODS

A total of 97 newly diagnosed lung cancer patients (69 males, 28 females; average age 65.1 years) with pathologically proven were retrospectively analyzed, who had undergone ¹⁸F-FDG PET/CT scan before treatment from September 2016 to November 2017. SUV<inf>max</inf>, MTV and TLG of primary tumor were measured. Clinical stage was mainly determined by ¹⁸F-FDG PET/CT, in conjunction with conventional imaging and endoscopic biopsy. Mann-Whitney U test, χ² test, Spearman correlation test and ROC curve analysis were used for statistical analysis.

RESULTS

There were 53 adenocarcinomas (AC), 28 squamous carcinomas (SCC), 13 small cell carcinomas (SCLC), one adenosquamous carcinoma, one mucoepidermoid carcinoma, and one sarcomatoid carcinoma in 97 patients. Both AC and SCLC revealed more cases in stage IV than in stage I-III (P<0.01). There was no significant difference in four stages of SCC (P>0.05). Metabolic parameters of SCC were higher than AC including SUV<inf>max</inf>, MTV and TLG (P<0.01). SCLC showed a higher value than AC in TLG (P<0.05). No significant differences were found between AC and SCLC in SUV<inf>max</inf> and MTV, also between SCC and SCLC in SUV<inf>max</inf>, MTV and TLG (P>0.05). MTV and TLG except SUV<inf>max</inf> were positively correlated with stage in AC (P≤0.001). Only MTV showed a positive correlation with stage in SCC (P<0.05). Whereas there were no definitive relationships between metabolic parameters and stage in SCLC (P>0.05). AC with a higher MTV (MTV≥5.965 cm³) indicated a significantly higher rate of distant metastasis than those with a lower MTV (77.5% (31/40) vs. 30.8% (4/13), χ²=9.553, P<0.01), as well as AC with a higher TLG (TLG≥46.922) than those with a lower TLG (88.5% (23/26) vs. 44.4% (12/27), χ²=11.422, P<0.01).

CONCLUSIONS

Histopathologic subtypes have a significant influence on the relationships between MTV/TLG not SUV<inf>max</inf> of primary foci and stage in lung cancer. Primary MTV/TLG is related to clinical stage closely in AC, and a higher MTV/TLG results in a higher risk of distant metastasis.

Prognostic value of metabolic tumour volume and total lesion glycolysis measured by 18F-fluorodeoxyglucose positron emission tomography/computed tomography in small cell lung cancer: A systematic review and meta-analysis

The aim of this study was to evaluate the prognostic value of metabolic tumour volume (MTV) and total lesion glycolysis (TLG) for small cell lung cancer (SCLC). MEDLINE, EMBASE and Cochrane Library databases were systematically searched. The pooled hazard ratio (HR) was used to measure the influence of MTV and TLG on survival. The subgroup analysis according to VALSG stage and the measured extent of MTV was performed. Patients with high MTV values experienced a significantly poorer prognosis with a HR of 2.42 (95% CI 1.46-4.03) for overall survival (OS) and a HR of 2.78 (95% CI 1.39-5.53) for progression-free survival (PFS) from the random effect model, and the pooled HR from the fixed effect model was 2.10 (95% CI 1.77-2.50) for OS and 2.27 (95% CI 1.83-2.81) for PFS. Patients with high TLG experienced a poorer prognosis with a HR of 1.61 (95% CI: 1.24-2.07) for OS from the random effect model, and the pooled HR from the fixed effect model was 1.64 (95% CI 1.37-1.96). Heterogeneity among studies was high for MTV in both OS and PFS meta-analyses (I²  = 87% and 88% respectively). After removing one outlier study the heterogeneity was substantially reduced (I²  = 0%) and the pooled HR for the effect of MTV on OS was 1.80 (1.51-2.16, P < 0.00001), and on PFS it was 1.86 (1.49-2.33, P < 0.00001), using either the fixed or random effects model. High MTV is associated with a significantly poorer prognosis OS and PFS, and high TLG is associated with a significantly poorer prognosis regarding OS for SCLC.

Prognostic value of the maximum standardized uptake value of pre-treatment primary lesions in small-cell lung cancer on 18F-FDG PET/CT: a meta-analysis

Background 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) has been widely used in clinical practice. However, the prognostic value of the pre-treatment standardized uptake value (SUV) for patients with small-cell lung cancer (SCLC) remains controversial. Purpose To investigate the prognostic role of pre-treatment 18F-FDG PET on SCLC patients by meta-analysis. Material and Methods Extensive literature searches of the PubMed, EMBASE, Web of Science, and Cochrane Library databases were conducted to identify literature published until 5 May 2017. Comparative analyses of the pooled hazard ratios (HRs) for event-free survival (EFS) and overall survival (OS) were performed to assess their correlations with the pre-treatment maximum SUV (SUVmax). Either the fixed- or the random-effects model was adopted, depending on the heterogeneity observed across the studies. Subgroup analyses were performed to assess the robustness of the results. Results Twelve studies with 1062 patients were included. The pooled HR for OS of 11 studies was 1.13 (95% confidence interval [CI] = 1.05-1.22; P = 0.001; I²= 0%) and the pooled HR for EFS of nine studies was 1.09 (95% CI = 1.02-1.17; P = 0.014; I²= 0%), indicating that patients with high SUVs may have poorer prognoses. Begg's test detected no significant publication bias. The prognostic role of the SUVmax remained similar in the subgroup analyses. Conclusion Our meta-analysis indicated that the pre-treatment SUVmax of primary lesions can be an important prognostic factor for OS and EFS in patients with SCLC. A high SUVmax may indicate poorer prognosis.

Early Response Assessment in Pancreatic Ductal Adenocarcinoma Through Integrated PET/MRI

OBJECTIVE

The purpose of this study is to investigate early changes in ¹⁸F-FDG PET/MRI metrics after treatment in patients with advanced pancreatic ductal adenocarcinoma (PDAC) and to correlate those changes with eventual tumor response at standard-of-care CT.

SUBJECTS AND METHODS

Thirteen patients with advanced PDAC underwent integrated FDG PET/MRI before and 4 weeks after treatment initiation. Patients were classified as responders or nonresponders according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 at subsequent CT performed 8-12 weeks after treatment initiation. Changes in the primary tumor's maximum standardized uptake value (SUV_max), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) determined at PET and apparent diffusion coefficient (ADC) determined at DWI at 4 weeks were compared between responders and nonresponders.

RESULTS

Seven patients had a partial response according to RECIST, and six did not. Responders displayed significantly greater decreases in MTV (p = 0.003) and TLG (p = 0.006) in the primary pancreatic tumor at 4 weeks. Responders also displayed a greater increase in the mean (p = 0.004) and minimum (p = 0.024) ADC of the primary tumors. Tumor size change at 4 weeks was not significantly different between responders and nonresponders (p = 0.11). PET responders enjoyed longer progression-free survival (PFS) (p = 0.0004) and overall survival (OS) (p = 0.013) than did nonresponders, using either a 60% reduction in MTV or 65% reduction in TLG as a threshold. MRI responders had significantly longer PFS (p = 0.0002) and OS (p = 0.027) than did nonresponders, using a 20% increase in either mean or minimum ADC as a threshold.

CONCLUSION

Integrated PET/MRI can provide early response assessment in patients with advanced PDAC, thus potentially allowing early treatment adaptation in nonresponders.

Relation of EGFR Mutation Status to Metabolic Activity in Localized Lung Adenocarcinoma and Its Influence on the Use of FDG PET/CT Parameters in Prognosis

OBJECTIVE

The purposes of this study were to assess the relation between epidermal growth factor receptor (EGFR) mutation status and FDG PET/CT findings and to evaluate the influence of this relation on the use of FDG PET/CT parameters to establish a prognosis in cases of localized lung adenocarcinoma.

MATERIALS AND METHODS

Patients with stage I and II lung adenocarcinomas were retrospectively enrolled. At the initial FDG PET/CT examination, maximum and peak standardized uptake, tumor-to-background ratio, and volumetric parameters of metabolic tumor volume and total lesion glycolysis were measured.

RESULTS

The values of all the metabolic and volumetric FDG PET/CT parameters were significantly lower in EGFR mutant than in EGFR wild-type lung adenocarcinomas. All parameters were statistically significant for predicting recurrence-free survival. In multivariate analyses, peak standardized uptake and total lesion glycolysis were more significant prognostic factors than was TNM stage (p < 0.001). Optimal cutoff values of parameters for predicting recurrence-free survival were slightly different between the two groups.

CONCLUSION

EGFR mutation is related to low metabolic activity of localized lung adenocarcinoma at FDG PET/CT. Because of differences in the metabolic activity of EGFR mutant and wild-type tumors, EGFR mutation status must be considered when FDG PET/CT parameters are used for prognosis.

Prognostic significance of 18F-fluorodeoxyglucose uptake of bone marrow measured on positron emission tomography in patients with small cell lung cancer

OBJECTIVES

We investigated whether ¹⁸F-fluorodeoxyglucse (FDG) uptake of bone marrow (BM) on positron emission tomography/computed tomography (PET/CT) has implications for predicting clinical outcomes in patients with small cell lung cancer (SCLC).

METHODS

We retrospectively enrolled 70 SCLC patients who underwent FDG PET/CT prior to treatment. On PET/CT, maximum FDG uptake of all tumor lesions (Tmax), coefficient of variation (COV) of FDG uptake of primary tumor, and mean FDG uptake of BM (BM SUV) were measured. The relationships of BM SUV with PET/CT parameters of SCLC and serum markers were evaluated. Univariate and multivariate analyses were performed to assess the significance of BM SUV for predicting progression-free survival (PFS) and overall survival (OS).

RESULTS

BM SUV had significant positive correlations with Tmax, COV of primary tumor, white blood cell count, and serum C-reactive protein level (p < .05). On univariate analysis, BM SUV showed significant association with only PFS (p = .006). On multivariate analysis, Veterans Administration Lung Cancer Study Group (VALSG) stage, N stage, M stage, Tmax, and BM SUV were independent prognostic factors for PFS (p < .05) and, for OS, VALSG stage and M stage were independent prognostic factors (p < .05). Among patients with limited disease, patients with high FDG uptake of BM had significantly worse PFS than did those with low FDG uptake of BM (p < .05), but, there was no significant difference in PFS between patients with extensive disease and patients with limited disease and high FDG uptake of BM (p > .05).

CONCLUSION

FDG uptake of BM was an independent predictor of disease progression in SCLC patients. Patients with limited disease and high FDG uptake of BM had similar PFS to those with extensive disease.

Incorporation of circulating tumor cells and whole-body metabolic tumor volume of 18F-FDG PET/CT improves prediction of outcome in IIIB stage small-cell lung cancer

Objective

We investigated the correlation between the number of circulating tumor cells (CTCs) and whole-body metabolic tumor volume (WBMTV) measured by ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT). The aim was to evaluate the value of the incorporation of CTC number and WBMTV in the prognostic prediction of stage III small-cell lung cancer (SCLC).

Methods

One hundred and twenty-nine patients were enrolled in this study. All patients were treated with four cycles of a platinum-based regimen and concurrent chest irradiation, followed by prophylactic cranial irradiation. Blood samples for CTC analysis were obtained from 112 patients before the initiation of chemotherapy (as a baseline), after cycle 1 and after cycle 4. CTCs were measured using the CELLSEARCH^® system. The patients underwent pretreatment FDG PET/CT WBMTV, which included all malignant lesions. The Spearman rank test was used to determine the correlation among CTC counts, WBMTV and disease stage. Overall survival (OS) and progression-free survival (PFS) curves were produced using the Kaplan-Meier method, and survival differences between groups were assessed by the log-rank test.

Results

The number of CTCs at baseline did not correlate with WBMTV before the initiation of therapy (P=0.241). The number of CTCs at baseline and the WBMTV before the initiation of therapy were independent relevant factors for PFS and OS. The subgroup analysis (Group A: CTC count >19.5 and a WBMTV >266.5 cm ³; Group B: CTC count >19.5 and a WBMTV ≤266.5 cm ³; Group C: CTC count ≤19.5 and a WBMTV >266.5 cm ³; Group D: CTC count ≤19.5 and a WBMTV ≤266.5 cm³) showed that the differences were statistically significant in the median PFS (Group A vs. D, P<0.001; Group Bvs. D, P=0.018; Group C vs. D, P=0.029) and in the median OS (Group A vs. D, P<0.001; Group Bvs. D, P=0.012).

Conclusions

CTC number and WBMTV are related to progression and death in patients with SCLC. The incorporation of CTC number and WBMTV scans can provide a detailed prognostic prediction for SCLC.

Prognostic value of metabolic indices and bone marrow uptake pattern on preoperative 18F-FDG PET/CT in pediatric patients with neuroblastoma

PURPOSE

To evaluate the prognostic value of metabolic parameters and bone marrow uptake (BMU) patterns on pretherapeutic 18-F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in pediatric patients with neuroblastoma (NB).

PATIENTS AND METHODS

Forty-seven pediatric patients with newly diagnosed neuroblastoma who underwent 18F-FDG PET/CT were retrospectively reviewed. Clinicopathological factors and metabolic parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), total lesion glycolysis (TLG) and bone marrow uptake patterns on PET/CT were compared to predict recurrence-free survival (RFS) and overall survival (OS) by univariate and multivariate analysis.

RESULTS

During the follow-up period, 27 (57.4%) patients experienced recurrence. MTV (P = 0.001), TLG (P = 0.004) and BMU patterns (P = 0.025) remained significant predictive factors for tumor recurrence, along with tumor size, histology, stage, lactate dehydrogenase (LDH) and other distant metastasis (except bone metastasis). Univariate analysis showed that histology, stage, tumor size (>37.25 cm), other distant metastasis, MTV (>88.10cm³) and TLG (>1045.2 g) and BMU patterns correlated with both RFS and OS (P < 0.05). On multivariate analysis, TLG remained the only independent prognostic factor for RFS (P = 0.016) and OS (P = 0.012), and BMU patterns and MTV were statistically significant for OS (P = 0.024 and P = 0.038, respectively).

CONCLUSION

Pretherapeutic 18F-FDG PET/CT can provide reliable prognostic information for neuroblastoma pediatric patients, and patients with high MTV, TLG and focal bone marrow (unifocal and multifocal) uptake on PET/CT may have inferior outcomes during subsequent treatment.

The prognostic value of the serum neuron specific enolase and lactate dehydrogenase in small cell lung cancer patients receiving first-line platinum-based chemotherapy

The aim of this study was to investigate the associations of serum levels of neuron-specific enolase (NSE), pro-gastrin releasing peptide (ProGRP), and lactate dehydrogenase (LDH) with clinical response and survival in small cell lung cancer (SCLC) patients receiving first-line platinum-based chemotherapy.One hundred thirty-six patients with SCLC were recruited in this study. All the patients received first-line platinum-based chemotherapy. Clinical efficacy was assessed according to Response Evaluation Criteria in Solid Tumors v1.1 criteria. Serum samples were collected from SCLC patients before chemotherapy. NSE, ProGRP, and LDH levels were measured by commercial electrochemiluminescence immunoassay, enzyme-linked immune sorbent assay, and kinetic spectrophotometric method, respectively.Overall response rate was 71.3% with 97 patients who achieved complete response (CR) +  partial response (PR). NSE and LDH level declined in patients who achieved CR + PR compared with patients in stable disease (SD) and progress disease (PD). Multivariate logistic regression analysis revealed that NSE > 50.324 ng/mL, stage ED, and distant metastases were independent risk factors for patients achieving CR + PR, and chemotherapy > 4 cycles was an independent protective factor in predicting CR + PR. Receiver operating characteristic (ROC) curves presented that expression of NSE, ProGRP, and LDH are of good predicting value for patients achieving CR + PR. Patients with a higher level of NSE and LDH presented worse progression-free survival and overall survival. In addition, multivariate Cox regression analysis showed that NSE level > 50.324 ng/mL and distant metastasis were independently correlated with worse OS.Serum NSE and LDH could be promising biomarkers for predicting therapy response and survival of SCLC patients receiving first-line platinum-based chemotherapy.

Prognostic Value of Pre- and Post-Treatment FDG PET/CT Parameters in Small Cell Lung Cancer Patients

Purpose

To evaluate the prognostic value of PET parameters obtained from pre- and post-treatment FDG PET/CT examinations in patients with SCLC.

Methods

Fifty-nine patients with initially diagnosed SCLC from 2009 to 2014 were included and had chemotherapy and/or concurrent chemoradiotherapy. FDG PET/CT examinations were performed before (PET1) and after (PET2) treatment to evaluate treatment response. A region of interest was placed over the primary lesion and metastatic lymph nodes within the thoracic cavity. PET parameters including change from PET1 to PET2 (Δ in %) were acquired: SUVmax, SUVpeak, MTV2.5, TLG, ΔSUVmax, ΔSUVpeak, ΔMTV and ΔTLG. Patient characteristics including staging, age, sex, LDH and response evaluation by RECIST were surveyed. Statistical analysis was done using Kaplan-Meier method and Cox regression analysis with respect to OS and PFS.

Results

The median follow-up was 9.6 months (2.5-80.5 months). 27 patients were LD and 32 were ED. Forty-six patients (78.0%) had died, and median OS was 8.6 months; 51 patients (86%) showed disease progression, and median PFS was 2.5 months. On univariate analysis, patients with ED, high interval change (ΔSUVmax and ΔSUVpeak) and low PET2 parameters showed longer OS and PFS. Multivariate analyses demonstrated that ΔSUVpeak (HR 2.6, P = 0.002) was an independent prognostic factors for OS, and MTV2.5 of PET2 (HR 2.8, P = 0.001), disease stage (HR 2.7, P = 0.003) and RECIST (HR 2.0, P = 0.023) were independent prognostic factors for PFS.

Conclusions

Metabolic and volumetric PET parameters obtained from pre- and post-treatment FDG PET/CT examinations in patients with SCLC have significant prognostic information.

Prognostic Value of Metabolic Parameters of Metastatic Lymph Nodes on 18F-FDG PET/CT in Patients With Limited-stage Small-cell Lung Cancer With Lymph Node Involvement

INTRODUCTION

We assessed the prognostic value of the metabolic parameters of different lesions, including primary tumors and metastatic lymph nodes (LNs), measured by fluorine-18 fluorodeoxyglucose positron emission tomography (PET)/computed tomography in patients with limited-stage small-cell lung cancer (LS-SCLC) with LN metastasis.

MATERIALS AND METHODS

The present retrospective study included 46 patients with clinical stage II-III N1-N2 LS-SCLC who had undergone pretreatment fluorine-18 fluorodeoxyglucose PET/computed tomography scanning from January 2011 to December 2014. All patients underwent complete first-line therapy (concurrent chemoradiotherapy and prophylactic cranial irradiation). The metabolic parameters, including maximal standardized uptake value, mean standardized uptake value, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) values of the PTs and metastatic LNs were measured on PET. Kaplan-Meier survival curves were used for evaluation of progression-free survival (PFS) and overall survival (OS). Univariate and multivariate Cox proportional hazards models were used to analyze the prognostic factors.

RESULTS

The median OS and PFS were 25.9 months (range, 8.2-63.5 months) and 21 months (range, 6.4-55.3 months), respectively. Univariate analysis demonstrated that the Eastern Cooperative Oncology Group performance status, N1 station involvement, subcarinal LN metastasis, LN MTV, LN TLG, sum of the MTV, and summary of the TLG were significant predictive factors (P < .05). The Eastern Cooperative Oncology Group performance status, subcarinal nodal metastasis, LN MTV, and LN TLG were independent predictive factors of PFS and OS on multivariate analysis.

CONCLUSION

The metabolic parameters of metastatic LNs, other than lung lesions, are independent prognostic factors in patients with LS-SCLC with LN metastasis. These parameters could further stratify the prognosis of these patients, and these findings might provide functional imaging evidence for the future study of the mechanisms of metastasis.

Prognostic value of pre-treatment 18F-FDG-PET uptake in small-cell lung cancer

PURPOSE

Small-cell lung cancer (SCLC) is an aggressive disease, despite an initially favorable response to treatment, and its prognosis is still poor. Multiple parameters have been studied as possible prognostic factors, but none of them are reliable enough to change the treatment approach. ¹⁸F-fluorodeoxyglucose-positron emission tomography (FDG-PET) is a novel imaging technique for staging of SCLC. The aim of this study was to evaluate the prognostic value of pre-treatment FDG-PET parameters on clinical outcome in limited stage (LS) SCLC patients treated with curative thoracic radiotherapy (RT) and chemotherapy.

METHODS

Clinical records of 46 LS-SCLC patients with pre-treatment FDG-PET imaging were retrospectively reviewed. Patients were treated with definitive RT for a total dose of 50-60 Gy and chemotherapy. The clinical endpoints were progression-free survival (PFS) and overall survival (OS).

RESULTS

The median age was 59 (range 30-82) years, and median follow-up time was 23.2 months (range 5-82.8 months). Median OS was 30.9 months for pre-treatment tumor maximum standardized uptake value (SUV_max) <9.3 and 20.6 months for SUV_max ≥9.3 (p = 0.027) and PFS was 55.6 months for SUV_max <9.3 and 38.6 months for SUV_max ≥9.3 (p = 0.16). Median OS was 73 months for pre-treatment lymph node SUV_max <5.8 and 21 months for ≥5.8 (p = 0.01) and PFS was 38.6 months (range 6.8-70.3 months) for SUV_max-LN ≥5.8; all patients with SUV_max-LN <5.8 were alive (p = 0.07). Median survival time was 28.2 months (range 21.7-34.7 months) for patients younger than 65 and 8.7 months (range 5.7-11.8 months) for those ≥65 years (p = 0.00).

CONCLUSIONS

Pre-treatment FDG-PET uptake may be a valuable tool to evaluate prognosis in SCLC patients. Patients with a higher pre-treatment FDG uptake may be considered at increased risk of failure and may benefit from more aggressive treatment approaches.

Prognostic value of quantitative PET/CT in patients with a nonsmall cell lung cancer and another primary cancer

OBJECTIVE

The staging and management of patients with newly diagnosed nonsmall cell lung cancer (NSCLC) in the setting of recently diagnosed other (metachronous or synchronous) primary cancer are challenging. This retrospective cohort study was carried out to test our hypothesis that baseline 2-deoxy-2-[F]fluoro-D-glucose (F-FDG) PET/CT parameters, including whole-body metabolic tumor volume (MTVWB), total lesion glycolysis (TLGWB), and maximum standardized uptake value (SUVmaxWB), are associated with the overall survival (OS) of such patients.

PATIENTS AND METHODS

A total of 110 NSCLC patients (52 men and 58 women, aged 68.6±7.8 years) with other primary malignant cancers who had baseline F-FDG PET/CT scans were retrospectively reviewed. MTVWB, TLGWB, and SUVmaxWB were measured. Kaplan-Meier analysis with the log-rank test and Cox regression models were used to assess the association of OS with F-FDG PET/CT parameters and clinical risk factors.

RESULTS

Kaplan-Meier analysis and univariate Cox regression models showed significant associations of OS with ln(MTVWB), ln(TLGWB), ln(SUVmaxWB), TNM stage, and treatment type (surgery vs. no treatment). Multivariable Cox regression models showed a significant relationship of OS with ln(MTVWB) [hazard ratio (HR)=1.368, P=0.001], ln(TLGWB) (HR=1.313, P<0.001), and ln(SUVmaxWB) (HR=1.739, P=0.006), adjusted for age, treatment type, tumor histology, and TNM stage. The TNM stage was not associated significantly with OS when MTVWB, TLGWB, or SUVmaxWB were included in the multivariable models.

CONCLUSION

MTVWB, TLGWB, and SUVmaxWB from baseline F-FDG PET/CT are associated individually with OS of patients with both NSCLC and other primary malignant tumors independent of age, treatment type, tumor histology, and TNM stage.

Prognostic value of whole-body SUVmax of nodal and extra-nodal lesions detected by 18F-FDG PET/CT in extra-nodal NK/T-cell lymphoma

We analyzed data from 54 newly-diagnosed persons with extra-nodal natural killer/T-cell (NK/T) lymphoma, who had a pretreatment 18F-FDG PET/CT study, to determine whether the sum of SUVmax of all the nodal and extra-nodal lesions predicted progression-free survival (PFS) and/or overall survival (OS). Three models (WB1SUVmax, WB2SUVmax, WB3SUVmax) based on the basis of the sum of SUVmax of the whole-body SUVmax of 11 nodal and 10 extra-nodal lesions were tested. The discrimination value of these models was evaluated using time-dependent receiver-operator characteristic (ROC) curves and corresponding areas under the curve (AUC) in training and validation cohorts. Findings were validated in an independent cohort of 15 subjects. ROC curve analysis showed the optimal cut-off values for WB1SUVmax, WB2SUVmax and WB3SUVmax were 15.8 (sensitivity 92%, specificity 67%, AUC 0.811; P<0.001), 12.7 (sensitivity 96%; specificity 57%; AUC 0.785; P<0.001) and 15.8 (sensitivity 88%; specificity 70%; AUC 0.793; P<0.001). Multivariate analyses indicated WB3SUVmax was independently associated with PFS (hazard ratio [HR]=3.67, 95% confidence interval [95% CI]=1.19, 11.29; P=0.023) and OS (HR= 4.51 [1.02, 19.91]; P=0.047). WB3SUVmax calculated based of the sum of the SUVmax of 3 nodal and 10 extra-nodal lesions was significantly associated with PFS and OS.

Prognostic significance of serum LDH in small cell lung cancer: A systematic review with meta-analysis

BACKGROUND

Lactare dehydrogenase (LDH) has been proven to be a prognostic and a potential pro-tumor factor in patients with lung cancer. But the prognostic value of serum LDH in small cell lung cancer (SCLC) has not been quantified systematically.

OBJECTIVE

Thus, this study was to evaluate the correlations between serum LDH and overall survival of SLCLC by systematic review with meta-analysis.

METHODS

PubMed, EMBASE, Cochrane Library, Web of Science databases were searched from inception to October 2014 and references in those publications would be included if the association between serum LDH and overall survival of SCLC can be derived. Quality assessment and data extraction were performed in the articles selected according to inclusion and exclusion criteria.

RESULTS

Twenty-eight studies including 4785 patients with SCLC were deemed eligible. Pooled results showed that SCLC patients with elevated LDH levels were associated with an increased hazard ratio (HR 1.45, 95%CI 1.27∼ 1.66) of overall survival.

CONCLUSIONS

The study suggests significant correlations between elevated serum LDH levels and poor overall survival in patients with SCLC. And serum LDH levels can be measured combining with other tools for assessing the risk stratification and prognosis of SCLC, which shows directions for treatments of SCLC.

The role of PET/CT as a prognosticator and outcome predictor in lung cancer

Positron emission tomography/computed tomography (PET/CT) is an important imaging tool for management of lung cancer and can be utilized in diagnosis, staging, restaging, treatment planning and evaluating treatment response. In the past decade PET/CT has proven to be beneficial for the prediction of prognosis and outcome. PET findings before and after treatment, the quantitative PET parameters such as standardized uptake value (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) as well as delayed PET/CT imaging can be used to determine patient prognosis and outcome. Other tracers such as hypoxia and proliferation marker tracers may be used for prognostication. The prognostic factors derived from PET/CT imaging help early development of risk-adapted treatment strategies, which provides cost-effective treatment and leads to improved patient management. Here, we discuss findings of studies related to application of PET/CT in lung cancer as well as some technical updates on quantitative PET/CT in lung cancer.

Prediction of coronary artery calcium progression by FDG uptake of large arteries in asymptomatic individuals

PURPOSE

The purpose of this study is to evaluate whether fluorodeoxyglucose (FDG) uptake of the large arteries can predict coronary artery calcium (CAC) progression in asymptomatic individuals.

METHODS

Ninety-six asymptomatic individuals who underwent FDG positron emission tomography (PET) and CAC scoring on the same day for health screening and follow-up CAC scoring ≥1 year after baseline studies (mean 4.3 years) were included. Vascular FDG uptake was measured and corrected for blood pool activity to obtain peak and average target-to-blood pool ratios (TBRpeak and TBRavg, respectively) for the carotid arteries, and ascending and abdominal aorta. CAC scores at baseline and follow-up of each individual were measured and absolute CAC change (ΔCAC), annual CAC change (ΔCAC/year), and annual CAC change rate (ΔCAC%/year) were calculated. CAC progression was defined as ΔCAC >0 for individuals with negative baseline CAC; ΔCAC/year ≥10 for those with baseline CAC of 0<x<100; ΔCAC%/year ≥10 % for those with baseline CAC ≥100. Vascular FDG uptake and other clinical risk factors were compared between CAC-progressors and non-CAC-progressors. Multivariate analysis was performed to evaluate whether vascular FDG uptake can independently predict CAC progression.

RESULTS

Thirty-one subjects showed CAC progression. CAC-progressors showed significantly higher TBRpeak and TBRavg as compared to non-CAC-progressors for all three arteries. TBRpeak of the abdominal aorta was significantly associated with CAC progression in multivariate analysis, with age and baseline CAC. A higher TBRpeak of the abdominal aorta (≥2.11) was associated with CAC progression among subjects with negative baseline CAC only. In subjects with positive baseline CAC, only the amount of baseline CAC was significantly associated with CAC progression. However, the positive predictive value of the TBRpeak of the abdominal aorta was <40 % when age was <58 or baseline CAC was negative.

CONCLUSIONS

Higher FDG uptake of the large arteries is associated with an increased risk of CAC progression in asymptomatic subjects with negative baseline CAC. But its clinical application needs further validation.

Consistency of metabolic tumor volume of non-small-cell lung cancer primary tumor measured using 18F-FDG PET/CT at two different tracer uptake times

OBJECTIVES

The objective of this study was to test the hypothesis that the metabolic tumor volume (MTV) of primary non-small-cell lung cancer is not sensitive to differences in F-fluorodeoxyglucose (F-FDG) uptake time, and to compare this consistency of MTV measurements with that of standardized uptake value (SUV) and total lesion glycolysis (TLG).

METHODS

Under Institutional Review Board approval, 134 consecutive patients with histologically proven non-small-cell lung cancer underwent F-FDG PET/computed tomography scanning at about 1 h (early) and 2 h (delayed) after intravenous injection of F-FDG. MTV, SUV, and TLG of the primary tumor were all measured. Student's t-test and Wilcoxon's signed-rank test for paired data were used to compare MTV, SUV, and TLG between the two scans. The intraclass correlation coefficient (ICC) was used to assess agreement in PET parameters between the two scans and between the measurements made by two observers.

RESULTS

MTV was not significantly different (P=0.17) between the two scans. However, SUVmax, SUVmean, SUVpeak, and TLG increased significantly from the early to the delayed scans (P<0.0001 for all). The median percentage change between the two scans in MTV (1.65%) was smaller than in SUVmax (11.76%), SUVmean(10.57%), SUVpeak(13.51%), and TLG (14.34%); the ICC of MTV (0.996) was greater than that of SUVmax (0.933), SUVmean (0.952), SUVpeak (0.928), and TLG (0.982). Interobserver agreement between the two radiologists was excellent for MTV, SUV, and TLG on both scans (ICC: 0.934-0.999).

CONCLUSION

MTV is not sensitive to common clinical variations in F-FDG uptake time, its consistency is greater than that of SUVmax, SUVmean, SUVpeak, and TLG, and it has excellent interobserver agreement.

Total 18F-FDG PET/CT Metabolic Tumor Volume Is Associated With Postoperative Biochemical Response in Patients With Metastatic Pheochromocytomas and Paragangliomas

OBJECTIVE

The aim of this pilot study was to determine if metabolic tumor volume (MTV) and total lesion glycolysis (TLG) could serve as predictors of biochemical remission and pharmacotherapy-free interval in patients with metastatic pheochromocytomas (PCCs) and paragangliomas (PGLs).

BACKGROUND

Patients with metastatic PCCs/PGLs have a high rate of biochemical recurrence, which can be associated with increased cardiovascular morbidity. Predictors of biochemical response are needed to guide and select patients who may benefit from therapy.

METHODS

Whole body MTV and TLG was calculated from preoperative 18F-FDG PET/CT scans and analyzed as marker of biochemical response and pharmacotherapy-free interval.

RESULTS

Seventeen patients underwent a total of 19 procedures, with a median follow-up time of 26.4 months. Whole body MTV of patients with biochemical recurrence (n = 13, mean 73.8  mL) was higher than those who had a biochemical response (n = 6, mean 14.7  mL, P = 0.05). Patients with low MTV (<37.2  mL) had an improved durable partial biochemical response (P < 0.05), and a statistical trend for complete biochemical remission (P = 0.07) and pharmacotherapy-free interval (P = 0.06). In 8 patients with metastatic disease outside the abdomen, 4 patients had less than 35% of their disease burden outside the abdomen and these patients had a more durable partial biochemical response compared to patients with greater than 35% of their disease burden outside the abdomen (P < 0.05).

CONCLUSIONS

Whole body MTV and TLG represents novel and valuable predictors of biochemical response for patients with metastatic PCCs and PGLs. A larger prospective study should be performed to validate these findings.

Present and future roles of FDG-PET/CT imaging in the management of lung cancer

Integrated positron emission tomography/computed tomography (PET/CT) using 2-[(18)F]fluoro-2-deoxy-D-glucose ((18)F-FDG) has emerged as a powerful tool for combined metabolic and anatomic evaluation in clinical oncologic imaging. This review discusses the utility of (18)F-FDG PET/CT as a tool for managing patients with lung cancer. We discuss different patient management stages, including diagnosis, initial staging, therapy planning, early treatment response assessment, re-staging, and prognosis.